For many years boxcars have been converted to vehicles for carrying grain or other particle-type material by installing temporary barriers across the doorways. The doorways normally are closed by sliding storm doors but these are incapable of serving as grain barriers, viz., the storm doors must be opened during the loading operation and it will be appreciated that as soon as the grain is delivered into the car, it would flow out. Thus, over the years, the art workers have provided temporary doors, usually reinforced by thin steel strapping. For the most part in the last decade or two, these temporary doors have had the straps embedded within the paperboard, i.e., covered by the outer sheet or face of the paperboard, this being true whether the paperboard panel was equipped with a corrugated core or not.
We have found that an extremely effective yet simple temporary door can be achieved by securing the horizontally extending, vertically spaced straps to the outside of the door panel. This insures that the entire panel serves as a barrier, not just selected thicknesses thereof. Further, we limitedly secure, as by adhesive, these straps to the door exterior and limit the length of the straps to slightly less than the width of the door panel -- and at the same time arcuately transversely severing the straps to substantially minimize the possibility of any injury to the installing artisan.
Inasmuch as the boxcar door posts over the years usually become splintered or otherwise incapable of adequately securing the straps, we provide additionally, when needed, a novel connection for extension bands which can be used to anchor the door to adjoining studs.
For especially wide doors, those in the art have used center braces, i.e., vertical members cross tied together across the car to limit the unsupported span. We have developed a new center brace member which coacts with the door in a novel fashion through the use of a horizontally flat tang extending through a slit in the straps to provide a superior and exceedingly effective reinforcement.
Other advantages may be seen in the details of manufacture, construction and operation as this specification proceeds.